[Exclusive] AstraZeneca's New Breast Cancer Drug Etracama to Enter Korea

Domestic Introduction Underway
Lower Mortality for ESR1 Mutation Patients
Early Detection of Mutations via ctDNA

AstraZeneca's new breast cancer drug, Etkama (ingredient name: camizestrant), is expected to be officially introduced in Korea. If the drug becomes commercially available in the country, it is anticipated that the traditional treatment method—where patients changed therapies only after resistance caused tumor progression—can be replaced by a new approach that detects resistance early and enables the start of treatment sooner.

According to industry sources on September 18, AstraZeneca Korea is proceeding with the domestic introduction procedures for Etkama, an orally administered selective estrogen receptor degrader (SERD) developed as a new breast cancer treatment. AstraZeneca Korea has reportedly designated the domestic product name as "Etkama." The company is currently undergoing the necessary approval process with the Ministry of Food and Drug Safety for domestic launch.

Once Etkama is introduced in Korea, it will provide a new treatment option for breast cancer patients who have developed resistance during treatment, resulting in decreased effectiveness of existing endocrine therapies. Hormone receptor (HR)-positive breast cancer is characterized by cancer cells growing in response to signals from estrogen, a female hormone, which is why endocrine therapies such as aromatase inhibitors are often used in combination with CDK4/6 inhibitors.

However, during the course of treatment, if an ESR1 mutation occurs, resistance can develop to aromatase inhibitors, leading to a gradual reduction in therapeutic effect. According to industry estimates, approximately 40% of patients develop ESR1 mutations after undergoing treatment with aromatase inhibitors.

Etkama is designed to directly degrade the estrogen receptor, thereby overcoming such resistance. Earlier this month, the U.S. Food and Drug Administration (FDA) granted accelerated approval to the combination therapy of Etkama with CDK4/6 inhibitors (abemaciclib, palbociclib, or ribociclib). The indication covers adult patients with HR-positive, HER2-negative, locally advanced or metastatic breast cancer who show ESR1 mutations detected through FDA-approved testing during combined treatment with aromatase inhibitors and CDK4/6 inhibitors. The FDA explained that the approval was aimed at "promoting medical innovation and providing new options for patients."

As a result, the use of blood tests to detect resistance mutations at an early stage is expected to become more common than before. The FDA has also approved "Guardant360 CDx" as a companion diagnostic device to identify patients with ESR1 mutations in conjunction with Etkama therapy. Previously, it was common to change treatment only after confirming tumor enlargement via regular imaging tests such as computed tomography (CT) or magnetic resonance imaging (MRI). However, treatment with Etkama allows for a switch in therapy upon the early detection of ESR1 mutations in ctDNA—DNA fragments shed from tumors—before progression is seen on imaging scans. This enables treatment changes before any visible advancement of cancer on imaging studies.

Jo Jaeyong, Director of the Cancer Center at Gangnam Severance Hospital, commented, "For patients who previously received preventive anti-estrogen therapies, there were very few options available if the cancer recurred, so this represents a significant change." He added, "Although the use of mutation testing utilizing ctDNA has been active in the United States, it has been relatively slow to take off in Korea. With the introduction of this new treatment, I see positive potential for the expanded application of ctDNA-based mutation testing in Korea as well."

This content was produced with the assistance of AI translation services.